Continuing the discussion from About Seamly:
@Ttailor: reviewing this thread might help you figure out your file problem.
You should probably uninstall Valentina before installing Seamly, & you may have to ctrl click the file to get a context menu allowing you to “Open with…” or something like that. If Seamly isn’t listed, there should be an option to choose an Application. In the dialog which that opens you should be able to find Seamly. IIRC there will be a checkbox regarding whether to permanently use the selected Application. Select Seamly from the list, & make sure that it is perma-selected.
I hope that helps. My last Mac died at about the time that El Capitan came out, & I’ve been using Linux ever since, so I’m a bit rusty.
